Fan shroud on an agricultural vehicle

ABSTRACT

An agricultural vehicle having a cooling system comprising a fan. The cooling system is housed in a bonnet of the vehicle. When the bonnet is closed it forms a part of a fan shroud of the fan and directs air in a direction parallel or substantially parallel to the longitudinal axis of the vehicle.

BACKGROUND OF THE INVENTION

Field of Invention

The invention relates to an engine cooling system on an agriculturalvehicle, more specifically the invention relates to a fan shroud of thecooling system on the vehicle.

Description of Related Art

Agricultural vehicles, such as agricultural tractors require a number ofradiators in order to cool working media, such as a water cooler for theengine, a transmission oil cooler, a hydraulic oil cooler, anintercooler and possibly a condenser for an air-conditioning system. Itis common practice to arrange the radiators in series one after theother under the vehicle bonnet so that air from a fan positioned at thefront of the vehicle drives air through the radiators. Radiators in thisarrangement may result in a high resistance to air flow which cannecessitate a larger fan, or can interrupt the air flow resulting in theradiator overheating.

To concentrate the flow of air from the fan to the first radiator, thatis the first radiator downstream of the fan, the fan is usually providedwith a fan shroud which projects in a direction towards the radiators.The fan shroud typically borders the circumference of the fan andextends a short distance parallel or substantially parallel to thelongitudinal axis of the vehicle. With this arrangement, the fan shroudcan be ineffective since there is a gap between the fan shroud and theradiator.

Moreover, in order to conduct maintenance or cleaning of the areabetween the fan shroud and the radiator of such cooling arrangements,the whole bonnet hood must firstly be removed or lifted which can beinconvenient as not all parts of the bonnet may be moveable. Secondlythe fan shroud must be removed.

OVERVIEW OF THE INVENTION

It is an object of the present invention to provide an engine coolingsystem which is effective and which is easily accessible. It is afurther object of the invention to provide an improved fan shroud on anagricultural vehicle engine cooling system.

According to the invention there is provided an agricultural vehiclehaving a cooling system comprising a fan, said cooling system housed ina bonnet of the vehicle, wherein said bonnet when closed forms a part ofa fan shroud of the fan for directing air in a direction parallel orsubstantially parallel to the longitudinal axis of the vehicle.

With this arrangement, part of the fan shroud extends up to a firstradiator and thus can guide the air directly to the first radiatorwithout the need for extra parts.

Preferably, a side panel of the bonnet forms a part of the fan shroud.More preferably, the side panel is partly or fully detachable from thebonnet. The side panel may be pivotally attached to the bonnet. In thisway, the fan and area between the fan and radiator is easily accessiblewithout the need for removing or lifting the whole bonnet.

Preferably, the bonnet and/or side panel is provided with sealing meansto prevent loss of air to the atmosphere. In this regard, as much air aspossible is driven from the fan to the first radiator.

Preferably, the bonnet is provided with two opposing side panels. Thecooling system can thus be accessed from either, or both sides of thebonnet.

More preferably, the fan is provided with an extended fan shroud whichis connectable to the side panel of the bonnet to form part of the fanshroud. When closed, the side panel of the bonnet assist in guiding theair from the fan towards the rear of the vehicle.

Preferably still, a complete fan shroud which extends from the fan to afirst radiator comprises the bonnet, a mounting plate which extends fromunder the fan to a first radiator and a fan shroud part which extendsfrom an upper part of the fan to the radiator. The bonnet preferablycomprises side panels which form a complete fan shroud with the mountingplate and the fan shroud part.

In this way, when the bonnet is closed the mounting plate, side panelsof the bonnet and an upper part of the fan shroud are all connected sothat all the air from the fan is directed to the first radiator.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described, by way of example only, withreference to the following drawings in which:

FIG. 1 is a side view of an agricultural tractor with the bonnet closed,

FIG. 1a is a perspective view of the bonnet of FIG. 1,

FIG. 1b is a side view of the bonnet of FIG. 1a with a hood of thebonnet raised in which a cooling arrangement in accordance with theinvention is shown,

FIG. 2 is a side view of a front part of the tractor bonnet of FIG. 1b ,and

FIGS. 3 and 4 are perspective views of the cooling arrangement of FIG. 2in which the bonnet panels and chassis are removed, and

FIG. 5 shows a cross section along line X-X of FIG. 4 which shows thecooling arrangement, and

FIG. 6 shows a detailed view of the front of the vehicle of FIG. 4.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 is a side view of an agricultural tractor 1 having a front bonnet2 which houses an engine and a cooling arrangement (not seen) inaccordance with the invention. The bonnet 2 extends from a driver's cab1 a to the front of the tractor. A grill or mesh 3 is positioned at thefront of the bonnet through which air passes and enters the coolingarrangement shown in FIGS. 2, 3 and 4. The tractor has a longitudinalaxis extending along the length of the tractor passing through the midpoints of a front and rear axle positioned transverse to thelongitudinal axis. The arrow indicates the forward direction of travel.

FIG. 1a is a perspective view of the bonnet of FIG. 1. The bonnet 2comprises a hood 2 a and two opposing side parts 2 b. When the bonnet 2is closed as shown in FIGS. 1 and 1 a, the hood 2 a has a fairly flatupper surface which extends in a generally horizontal manner from thecab. Towards the front of the vehicle, the upper surface of the hood 2 astarts to slope downwards and has an almost vertical front part at thefront of the tractor. The hood 2 a has an overhang which extends a smallvertical distance along each of the two long opposing side edges. Eachside of the bonnet 2 is formed from a side part 2 b and the overhang ofhood 2 a. The front part of the hood 2 a and a part of the upper surfaceof the hood is provided with the grill or mesh 3.

FIG. 1b is a side view of the bonnet 2 with the hood 2 a in an openposition. The hood 2 a may be lifted to give access to the parts underit by pivoting it about a pivot axis located close to the cab 1 a. Whenthe hood 2 a is lifted, it moves away from the side parts 2 b. Thelarger the tractor, the higher is the front of the hood when pivotedopen. In the open position, the hood is often too high for person toreach and then apply the necessary force to pivot it down to close it.The bonnet hood may be provided with a retractable belt 18 which extendsbetween a spring mounted roller and an attaching means. Either one ofthe roller or attaching means is positioned on the hood 2 a with theother part, attaching means or roller being positioned on the tractor,for example the chassis. When the hood 2 a is open the belt extendsvertically from the hood 2 a to the chassis. To close the hood, thedriver simply pulls a mid portion of the belt towards him or her whichcauses the hood to pivot downwards. As the hood 2 a is closed, the beltretracts in length by the roller rolling the belt under tension from theroller spring.

As shown in FIG. 6, the front of the hood is provided with a lockingmeans 50 for securing the hood to a front part of the tractor in aclosed position. Additionally, or alternatively for easy closure of thehood and to prevent damage to the hood, guidance means is providedcomprising two rollers 52 and two tracks 53. In FIG. 6, the hood isprovided with two rollers 52 either side of the locking means 50. Tracks53 extend in a substantially upright manner from a front part of thetractor which enables the rollers 52 to roll between the tracks 53 andguide the locking means 50 to the front of the tractor for engagement asthe hood is lowered.

Each side part 2 b comprises moveable side panels 6 a, 6 b and 6 c (inwhich a grill may be integrated). Side panels 6 a are located towardsthe front of the tractor and extend approximately from a fan 5 toradiators 6 as shown in FIG. 3. If more than one radiator 6 is fitted,the radiators are usually mounted in a series becoming increasinglycloser towards the engine. Panels 6 b and 6 c are located to the rear ofthe bonnet and cover the engine. Moveable side panels 6 a and 6 b arepivotally attached to each side part 2 b so that they can be moved withrespect to the side parts to give access to components of the coolingsystem and/or engine system under the bonnet. The pivoting means maycomprise spring means. Alternatively, side panels 6 a and 6 b may befully, or partly removable from the side parts 2 b to give access.

The edges of the panels 6 a and 6 b or the edges of the side parts 2 binto which panels 6 a and 6 b fit are provided with a sealing means suchas a rubber tubing 14 (FIG. 2) to prevent the escape of air to theatmosphere.

If side panel 6 a is removable, it is attached to side part 2 b byclamps and hooks at the locations marked E in FIGS. 1a and 1b . Toenable the side panels 6 a to be easily removed, a hand grip 17 can beprovided on the side panels 6 a which allows a person to easily get agrip of the panels.

FIG. 2 is a side view of a front part of the bonnet 2 in which the sidepanel 6 a has been omitted so that the cooling arrangement inside thebonnet can be seen. A mounting plate 4 is provided which extends fromunder the fan 5 which is positioned at the front of the tractor behindthe grill 3 to under the radiator or radiators 6 which are positioned infront of the engine (not shown) with respect to the forward direction oftravel of the tractor. The tractor is provided with two parallel frames7 which form the chassis. The mounting plate 4 extends widthways acrossboth frames 7 and is provided with a fan mounting surface 8 and radiatormounting surfaces 9. The side

profile of the mounting plate 4 is that of a laterally extended Z inthat the fan mounting surface 8 and radiator mounting surfaces 9 aregenerally horizontal and are connected by a sloping surface 13 such thatthe fan mounting surface is elevated with respect to the radiatormounting surfaces. Since the frames 7 are horizontal, a support element10 fixes the front of the plate 4 under the fan mounting surface 8 tothe frames 7. The support element 10 is affixed to the frames 7 bybolts. The radiator mounting surface 9 of the plate is secured directlyto the frames 7 by bolt means. On the underside of the plate 4 at thearea of the fan mounting surface 8, attachment means are provided forattaching a light or heater core thereto. In, or on the plate 4 at thearea of the radiator mounting surface 9, bore holes and/or channels areprovided for receiving pipes from the radiator or radiators 6 and/ordelivering liquid to the radiator or radiators 6.

Two air flows are indicated by arrows A and B. Air Arrow A shows an airflow for an air intake for the combustion of the engine and arrow B forcooling the radiators 6 and the engine. The fan 5 pushes air through theradiators 6 and the engine.

FIGS. 3 and 4 are perspective views of the cooling arrangement 11 inwhich the chassis and bonnet have been omitted. The difference betweenFIGS. 3 and 4 is that in FIG. 4 an extended fan shroud 12 is shown. Asshown in FIGS. 3 and 4 fan 5 is mounted on mounting plate 4 so that itis tilted towards the radiators 6. Fan 5 is secured to the fan mountingsurface 8 by fan attachment means extending through bores in the plate4. Radiators 6 are attached in series to plate 4 by bolt means. Theradiators 6 are in a spaced arrangement from the fan 5 with the fanmounting surface 8 at one end of the sloping surface 13 and the radiatormounting surfaces 9 at the other end.

The extended fan shroud is assembled from a number of parts boltedtogether. Preferably, the extended shroud comprises at least three orfour parts. In FIG. 4 the extended fan shroud 12 is shown having a lowerpart 12 a which extends from the bottom half of a fan ring 12 c in aforward direction with respect to the forward direction of travel of thetractor and an upper part 12 b which extends rearwards from the upperhalf of the fan ring 12 c towards the radiators 6 over plate 4. Theupper part 12 b is formed by two side parts 12 d (only one is shown inFIG. 4) and a central part 12 e. Side parts 12 d may therefore beconnected to either side of central part 12 e to from an upper part 12b. Alternatively, central part 12 e could itself comprise two halfparts, each of which is connected to a side part 12 e to form the upperpart 12 b.

A flange 15 is provided with sealing means 16. The flange 15 extendsfrom a lower part of the fan shroud 12 a diagonally along opposing sidesof the upper part 12 b and across parts 12 b and 12 d of upper part 12b. Preferably the bonnet 2 may be provided with sealing means 16.Sealing means 16 may, for example comprise rubber tubing.

In FIG. 5 the cooling arrangement 11 is shown. The cooling arrangementshown comprises a fan 5 and radiators 6 in which the radiators arelocated downstream of the fan. It is envisaged that the fan 5 and theradiators 6 could be arranged the other way around so that the radiatorsare mounted upstream of the fan. In such an arrangement, the radiatorsare mounted in front of the fan with respect to the forward direction oftravel.

When the bonnet 2 is closed and in contact with the sealing means 16 twoair compartments are defined. A first air compartment C and a second aircompartment D. First air compartment C is partially positioned abovecooling fan 5, between the grill 3 of hood 2 a and extended fan shroud12. Compartment C is a low pressure area. The dotted line in FIGS. 2 and4 represents the grill 3 of the bonnet 2 when closed. With reference toFIG. 1a in which the bonnet is closed, grill 3 is formed in the hood 2 aso that it has a vertical, or generally vertical part 3 a and agenerally horizontal part 3 b. Grill part 3 b extends from grill part 3a towards the rear of the vehicle past fan 5.

Second air compartment D is positioned downstream of the fan 5 and asshown herein is located behind the radiators 6. Compartment D is a highpressure area and is enclosed by the hood 2 a, the flange 15 and bonnetside panels 6 b, 6 c. Air which passes through the radiators 6 enterscompartment D and then flows out to the atmosphere through a grillmounted in panel 6 c, or through the frames 7.

By compartment it is meant a partially or fully enclosed area in which asurface which fully or partially encloses the area may, or may not beairtight.

When the bonnet 2 is closed and sealed, the panels 6 a form an extensionof the fan shroud between lower part 12 a and upper part 12 b so thatair is channelled between the upper part 12 b, side panels 6 a andmounting plate 4 to the radiator 6. As a result, a complete fan shroudwhich extends from the fan to the radiator is formed from the upper part12 b, side panels 6 a and plate 4. Thereby the mounting plate 4 guidesair directly to the radiators 6.

When the bonnet 2 is closed and the sealing means 16 contacts the bonnet2 (or flange) two air compartments C and D are defined.

The invention claimed is:
 1. An agricultural vehicle having a coolingsystem comprising a fan and a radiator mounted on a mounting plate, saidfan provided with a shroud part which extends rearwards from the upperhalf of the fan towards the radiator over the plate, said cooling systemhoused in a bonnet of the vehicle, characterised in that when the bonnetis in a closed position, a fan shroud is formed, with portions of thefan shroud being formed by the shroud part, the bonnet and the mountingplate, wherein the fan shroud extends from the fan to the radiator todirect air between the fan and radiator in a direction parallel orsubstantially parallel to the longitudinal axis of the vehicle.
 2. Anagricultural vehicle as claimed in claim 1 wherein a side panel of thebonnet forms a part of the fan shroud.
 3. An agricultural vehicle asclaimed in claim 2 wherein at least one of the bonnet and side panel isprovided with sealing means to prevent loss of air to the atmosphere. 4.An agricultural vehicle as claimed in claim 2 wherein the bonnet isprovided with two opposing side panels.
 5. An agricultural vehicle asclaimed in claim 4 wherein the bonnet comprises two side panels and saidside panels form the fan shroud with the mounting plate and the fanshroud part.